Dual-mode mobile telephone terminal

ABSTRACT

A portable-type dual-mode mobile telephone terminal apparatus including a satellite wireless communication controller  2  for performing satellite communications via a communications satellite and a cellular wireless communication controller  8  for performing cellular communications via a ground station, and interfacing means  21  for making interfacing between the satellite wireless communication controller  2  and the LCD/keypad junction unit  14  of the cellular wireless communication controller  8 . The interfacing means  21  performs software interfacing under the control of a program while address decoders and input and output ports perform electrical interfacing.

TECHNICAL FIELD

The present invention relates to a dual-mode mobile telephone terminalapparatus and, more particularly, to a portable-type, dual-mode mobiletelephone terminal apparatus capable of performing satellitecommunications via a communications satellite and cellularcommunications via a base station on the ground (hereinafter referred toas a “ground station”).

BACKGROUND ART

FIG. 11 is a block diagram of a conventional dual-mode mobile telephoneterminal apparatus. Referring to FIG. 11, there are shownsatellite-communication mobile telephone terminal module (hereinafterreferred to as “satellite terminal module”) 1, a satellite wirelesscommunication controller 2 mounted in the satellite terminal module 1,CPU 3 in the satellite wireless communication controller 2, forcommunicating with another terminal apparatus via a communicationssatellite (not shown) under the control of software, and a hand set 4composed of LCD 5, a keypad 6 and an interface circuit 7. The interfacecircuit 7 makes signals coming in from LCD 5 and the keypad 6 compatiblewith the interface of CPU 3.

There are also shown a hand-set type, cellular communication mobiletelephone terminal module 8 for terrestrial communications (hereinafterreferred to as “cellular terminal module”) having an externalinput/output terminal 15 through which a monitoring control signal andthe like are input and output, a cellular wireless communicationcontroller 9 mounted in the cellular terminal module 8, CPU 10 in thecellular wireless communication controller 9, for communicating withanother terminal apparatus via a ground station (not shown) under thecontrol of software, LCD 11 on the cellular terminal module 8, a keypad12 on the cellular terminal module 8, an interface circuit 13 betweenCPU 10 and LCD 11 and keypad 12, an LCD/keypad junction unit 14connected to the interface circuit 13, and the external input/outputterminal 15 such as a connector attached onto the casing of the cellularterminal module 8.

FIG. 12 shows in detail the interface circuit 13 and LCD/keypad junctionunit 14 in a conventional dual-mode mobile telephone terminal apparatus.Referring to FIG. 12, there are shown an LCD interface IC 13 a and akeypad interface IC 13 b, both of which form the interface circuit 13.

Also shown are an LCD connector 14 a and a keypad connector 14 b, bothof which forms the LCD/keypad junction unit 14.

The operation of the conventional art thus constructed is now discussed.When a telephone call is placed entering a telephone number of adestination, namely, a party to be called, and referring to the displayof LCD 5, a required signal is fed to CPU 3 in the satellite terminalmodule 1, and CPU 3 decides whether the call is to be placed by thesatellite terminal module 1 via the communications satellite (not shown)or by the cellular terminal module 8 via the ground station (not shown).

After the decision, when the call is successfully placed by either thecellular terminal module 8 or the satellite terminal module 1, a userstarts a voice communication using the hand set 4 through one of theterminal modules that has successfully placed the call.

Most of the satellite terminal modules widely and currently manufacturedin the world, as the satellite terminal module 1, are as large as of asheet A4 or B5 size at the smallest. Since the communicationssatellites, positioned at a geostationary orbit 36000 km above theequator, suffer a severe wireless wave attenuation, they are in need ofa relatively large antenna and a high-output power, and ascommunications satellites at a low earth orbit (LEO) or at anintermediate earth orbit (IEO) are going to be used from now on, aportable handheld type, satellite terminal module 1 works even with asmaller antenna such as a bar antenna and a low output power, and thehand set 4, satellite terminal module 1 and cellular terminal module 8in FIG. 11 may be integrated into a handheld side communicationterminal.

A variety of systems are available in conventional dual-mode mobiletelephone terminal apparatuses in terms of the cellular communicationsystem of the cellular terminal module 8, including PDC (PersonalDigital Cellular in a Japanese standard mobile communication system),GSM (Global System for Mobile Communication in a European standardmobile communication system), DAMPS (Digital Advanced Mobile PhoneService in a U.S. standard mobile communication system), and CDMA (CodeDivision Multiple Access in another U.S. standard mobile communicationsystem different from DAMPS), and they are different from each other inspecification, for example, in interfacing conditions of the externalinput/output terminal 15, and some systems dispense with the externalinput/output terminal 15.

If an attempt is made to integrate the hand set 4, satellite terminalmodule 1, and cellular terminal module 8 shown in FIG. 11 into onehandheld communications terminal, the interfacing conditions of theexternal input/output terminal 15 needs modifying depending on thecellular communication system of the cellular terminal module 8 to beintegrated, or an external input/output terminal itself needs to benewly installed, and for this reason, the standardization of hardware isdifficult, and the manufacturing cost of the hardware is high, and whenone cellular wireless communication controller is changed to anothercellular wireless communication controller, a hardware modification isneeded, pushing the cost of the apparatus.

The present invention has been developed to resolve the above problems,and it is an object of the present invention to provide a dual-modemobile telephone terminal apparatus, wherein a satellite terminal moduleand a cellular terminal module are integrated at a low cost with aminimum hardware modification involved, requiring no increase in thecomponent count of the apparatus, and a cellular wireless communicationcontroller is changed from one cellular communication system to anotherwith a minimum hardware modification involved.

DISCLOSURE OF THE INVENTION

To achieve the above object, the dual-mode mobile telephone terminalapparatus of the present invention comprises a satellite wirelesscommunication controller for performing satellite communications withanother terminal apparatus via a communications satellite, a cellularwireless communication controller, including an input/output junctionunit, for performing cellular communications with another terminalapparatus via a ground station, and interfacing means, arranged betweenthe satellite wireless communication controller and the input/outputjunction unit of the cellular wireless communication controller, formaking interfacing between the satellite wireless communicationcontroller and the input/output junction unit of the cellular wirelesscommunication controller.

The dual-mode mobile telephone terminal apparatus of the presentinvention further comprises input means into which a telephone number ofa destination is entered to place a call, and display means fordisplaying the telephone number input through the input means, whereinthe satellite wireless communication controller, the cellular wirelesscommunication controller, the interfacing means, the input means and thedisplay means are integrated with a hand set in a unitary body.

The cellular wireless communication controller outputs in/out-of-areainformation that indicates whether the apparatus is in or out of acellular communication service area, while the satellite wirelesscommunication controller receives the in/out-of-area information fromthe cellular wireless communication controller, and when the satellitewireless communication controller determines that the apparatus is inthe cellular communication service area, it causes the cellular wirelesscommunication controller to perform cellular communications, and whenthe satellite wireless communication controller determines that theapparatus is out of the cellular communication service area, it performssatellite communications.

The present invention further comprises a plurality of cellular wirelesscommunication controllers of different cellular communication systemtypes and the interfacing means respectively compatible with thecellular wireless communication controllers of different cellularcommunication system types, wherein when one of the plurality ofcellular wireless communication controllers performs cellularcommunications, the interfacing means compatible with the one cellularwireless communication controller makes interfacing between thesatellite wireless communication controller and the input/outputjunction unit of the one cellular wireless communication controller.

The dual-mode mobile telephone terminal apparatus of the presentinvention further comprises a plurality of cellular wirelesscommunication controllers of different cellular communication systemtypes, first interfacing means for making software interfacing under thecontrol of a program compatible with the cellular communication systemof one cellular wireless communication controller in use, out of theplurality of cellular wireless communication controllers, and aplurality of second interfacing means, respectively arranged for theplurality of cellular wireless communication controllers, for performingelectrical interfacing, wherein when one of the plurality of cellularwireless communication controllers performs cellular communications, thefirst interfacing means makes software interfacing under the control ofthe program compatible with the cellular communication system of the onecellular wireless communication controller while the second interfacingmeans makes electrical interfacing compatible with the one cellularwireless communication controller, in connection with the interfacingactivity between the satellite wireless communication controller and theinput/output junction unit of the cellular wireless communicationcontrollers.

The dual-mode mobile telephone terminal apparatus of the presentinvention comprises, in the interfacing means, first interfacing meansfor making software interfacing under the control of a programcompatible with the cellular communication system of one cellularwireless communication controller actually mounted, out of a pluralityof cellular wireless communication controllers of different cellularcommunication system types expected to be mounted, a plurality of secondinterfacing means, respectively arranged for the plurality of cellularwireless communication controllers, for performing electricalinterfacing, with the first interfacing means arranged separately fromthe plurality of second interfacing means, and selection means forselecting one second interfacing means, among the plurality of secondinterfacing means, compatible with the mounted cellular wirelesscommunication controller, wherein when one of the plurality of cellularwireless communication controllers performs cellular communications, thefirst interfacing means makes software interfacing under the control ofthe program compatible with the cellular communication system of the onecellular wireless communication controller, while the second interfacingmeans makes electrical interfacing compatible with the one cellularwireless communication controller selected by the selection means, inconnection with the interfacing activity between the satellite wirelesscommunication controller and the input/output junction unit of thecellular wireless communication controllers,

In the dual-mode mobile telephone terminal apparatus of the presentinvention, the interfacing means is divided into first interfacing meansfor making software interfacing under the control of a program andsecond interfacing means for making electrical interfacing wherein a CPUthat executes a program in the satellite wireless communicationcontroller to perform satellite communications further makes softwareinterfacing under the control of the program of the first interfacingmeans for the first interfacing means while the second interfacing meansis arranged separately from the satellite wireless communicationcontroller and the cellular wireless communication controller.

In the dual-mode mobile telephone terminal apparatus of the presentinvention, the CPU that executes the program in the satellite wirelesscommunication controller to perform satellite communications furthermakes software interfacing under the control of the program of the firstinterfacing means for the first interfacing program.

In the dual-mode mobile telephone terminal apparatus of the presentinvention, the interfacing means is divided into first interfacing meansfor making software interfacing under the control of a program andsecond interfacing means for making electrical interfacing, wherein aCPU that executes a program in the cellular wireless communicationcontroller to perform cellular communications further makes softwareinterfacing under the control of the program of the first interfacingmeans for the first interfacing means while the second interfacing meansis arranged separately from the satellite wireless communicationcontroller and the cellular wireless communication controller.

In the dual-mode mobile telephone terminal apparatus of the presentinvention, the CPU that executes the program in the cellular wirelesscommunication controller to perform cellular communications furthermakes software interfacing of the first interfacing means for the firstinterfacing means.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram generally showing the construction of adual-mode mobile telephone terminal apparatus according to a firstembodiment of the present invention, FIG. 2 is a block diagram showingin detail an interface 7 of the first embodiment, FIG. 3 is a blockdiagram showing in detail an interface 21 of the first embodiment, FIG.4 is a block diagram showing generally a dual-mode mobile telephoneterminal apparatus according to a second embodiment of the presentinvention, FIG. 5 is a block diagram showing generally a dual-modemobile telephone terminal apparatus according to a third embodiment ofthe present invention, FIG. 6 is a block diagram showing generally adual-mode mobile telephone terminal apparatus according to a fourthembodiment of the present invention, FIG. 7 is a block diagram showinggenerally a dual-mode mobile telephone terminal apparatus according to afifth embodiment of the present invention, FIG. 8 is a block diagramshowing generally a dual-mode mobile telephone terminal apparatusaccording to a sixth embodiment of the present invention, FIG. 9 is ablock diagram showing generally a dual-mode mobile telephone terminalapparatus according to a seventh embodiment of the present invention,FIG. 10 is a block diagram showing generally a dual-mode mobiletelephone terminal apparatus according to an eighth embodiment of thepresent invention, FIG. 11 is a block diagram generally showing aconventional dual-mode mobile telephone terminal apparatus, and FIG. 12is a block diagram showing in detail an interface circuit 13 andLCD/keypad junction unit 14 in the conventional dual-mode mobiletelephone terminal apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION (1) First embodiment

FIG. 1 shows generally the construction of a dual-mode mobile telephoneterminal apparatus of a first embodiment of the present invention.

In FIG. 1, components described with reference to FIG. 11 and FIG. 12are designated with the same reference numerals, and the discussionabout them is not repeated, and there are shown a satellite wirelesscommunication controller 2 including CPU 3 that performs satellitecommunications via a communications satellite under the control of aprogram, LCD 5 as display means, a keypad 6 as input means, an interfacecircuit 7 which is shown in greater detail in FIG. 2, a cellularwireless communication controller 8, including CPU 10 that performscellular communications via a ground station under the control of aprogram, and connected to associated components external to it via anLCD/keypad junction unit 14, interfacing means 21, which is shown ingreater detail in FIG. 3, is arranged between the satellite wirelesscommunication controller 2 and the LCD/keypad junction unit 14 of thecellular wireless communication controller 8, and makes interfacingbetween CPU 3 of the satellite wireless communication controller 2 andthe LCD/keypad junction unit 14 of the cellular wireless communicationcontroller 8, and all of these components are integrated with a hand setin a unitary body, forming a handheld-type, dual-mode mobile telephoneterminal apparatus 100. Dual-mode mobile telephone terminal apparatuses200-800 to be described later in connection with respective secondembodiments to eighth embodiments are also of a handheld type.

The satellite wireless communication controller 2 and the cellularwireless communication controller 8 remain unchanged from respectiveconventional ones mounted on circuit boards, and the cellular wirelesscommunication controller 8 is available in a variety of cellularcommunication system types including PDC, GSM, DAMPS, CDMA. Memoriesthat store programs for CPUs, such as the program for CPU 3 in thesatellite wireless communication controller 2 and the program for CPU 10of the cellular wireless communication controller 8, are employed,though not shown in FIG. 1, and the same is true of the second—eighthembodiments.

FIG. 2 shows the interface circuit 7 of the first embodiment in greaterdetail.

Referring to FIG. 2, there are shown an interface circuit 71, like theinterface circuit 13 shown in FIG. 12, comprising a keypad interface IC71 a and an LCD interface IC 71 b and CPU 72 that interfaces with CPU 3in the satellite wireless communication controller 2 in serialtransmission based on the RS-232-C interface.

FIG. 3 shows in greater detail the interfacing means 21 of the firstembodiment.

Referring to FIG. 3, there are shown address decoders 21 a and 21 d fordecoding address data that comes in through address buses from theLCD/keypad junction unit 14, an output port 21 b for outputting data tothe LCD/keypad junction unit 14 through a data bus based on the addressdecoded by the address decoder 21 a, an output port 21 c for outputtingan interrupt signal to the LCD/keypad junction unit 14, and an inputport 21 e for receiving data from the LCD/keypad junction unit 14through a data bus based on the address decoded by the address decoder21 d, and these components make electrical interfacing of theinterfacing activity carried out between CPU 3 of the satellite wirelesscommunication controller 2 and the LCD/keypad junction unit 14 of thecellular wireless communication controller 8.

CPU 21 f performs software interfacing of the interfacing activitycarried out between CPU 3 of the satellite wireless communicationcontroller 2 and the LCD/keypad junction unit 14 of the cellularwireless communication controller 8, specifically, serially interfaceswith CPU 3 in the satellite wireless communication controller 2,converts data format, and interfaces with CPU 10 in the cellularwireless communication controller 8. More specifically, under thecontrol of a program, CPU 21 f in the interfacing means 21 performs avariety of monitoring control processes to CPU 10 in the cellularwireless communication controller 8 through serial interface, convertsthe data format of the interfacing signal with CPU 3 into theinterfacing format of the LCD/keypad junction unit 14, and converts thesignal generated at the pressing of the keypad 6 into a signalcompatible with the cellular wireless communication controller 8 throughthe address bus for keypad interface, data bus and interruption with theLCD/keypad junction unit 14. The data format conversion function isperformed using a table.

The operation of the dual-mode mobile telephone terminal apparatus 100of the first embodiment thus constructed is now discussed.

When a call is placed, a telephone number of a party to be called isinput to the keypad 6 referring to the display on LCD 5.

A required signal is sent to CPU 3 built in the satellite wirelesscommunication controller 2, and CPU 3 then decides whether the call isto be placed through the satellite wireless communication controller 2for satellite communications or through the cellular wirelesscommunication controller 8 for cellular communications.

The first embodiment employs, as a reference on which the decision isbased, in/out-of-area information that indicates whether a radio wave,which is transmitted from the ground station is received by the cellularwireless communication controller 8 at a certain signal level or higher,wherein CPU 10 in the cellular wireless communication controller 8 islinked to CPU 3 in the satellite terminal module 1 through theLCD/keypad junction unit 14 and interfacing means 21, and CPU 3 works inthe following algorithm: when CPU 3 in the satellite terminal module 1determines from the in/out-of-area information that the apparatus iswithin the cellular service area, it causes the cellular wirelesscommunication controller 8 to place the call, and when CPU 3 determinesthat the apparatus is out of the cellular service area or when anattempt to establish a connection fails, the satellite wirelesscommunication controller 2 places the call.

When CPU 3 in the satellite wireless communication controller 2determines that the apparatus is in the cellular service area, thecellular wireless communication controller 8 places a call, and when CPU3 determines that the apparatus is out of the cellular service area orwhen an attempt to establish a connection fails, the satellite wirelesscommunication controller 2 places the call.

When the cellular wireless communication controller 8 places the call,the interfacing means 21 makes software interfacing such as requiredelectrical conversion and data format conversion, and the telephonenumber entered through the keypad 6 is converted electrically and insoftware to be compatible with the LCD/keypad junction unit 14, and suchconverted telephone number is sent to CPU 10 through the LCD/keypadjunction unit 14 of the cellular wireless communication controller 8,and CPU 10 in the cellular wireless communication controller 8 placesthe call based on the converted telephone number.

In the dual-mode mobile telephone terminal apparatus 100 of the firstembodiment, CPU 21 f in the interfacing means 21 makes softwareinterfacing such as data format conversion by carrying out a program, inaccordance with the cellular communication system type of the cellularwireless communication controller 9 mounted in the dual-mode mobiletelephone terminal apparatus 100, and the address decoders 21 a and 21d, input and output ports 21 b, 21 c and 21 e make electricalinterfacing, and there is thus no need for the connection with CPU 3 inthe satellite wireless communication controller 2 via the externalinput/output terminal 15 in accordance with the cellular communicationsystem type of the cellular wireless communication controller 9.

As a result, even when the cellular wireless communication controller 9is changed in cellular communication system type in the dual-mode mobiletelephone terminal apparatus 100 of the first embodiment, no hardwaremodification is required unlike the conventional art in which theexternal input/output terminal 15 is replaced or newly attached, as longas the electrical interfacing specifications of the address decoders 21a and 21 d and the input and output ports 21 b, 21 c and 21 e remainunchanged, and all that is necessary is a software modification in theprogram for CPU 21 f in the interfacing means 21, and the resultingdual-mode mobile telephone terminal apparatus is compatible with avariety of cellular communication system types with a common hardware,and the manufacturing cost of the apparatus is thus substantiallyreduced.

(2) Second embodiment

Although the above-described first embodiment employs a single cellularwireless communication controller 8, a second embodiment employs aplurality (two herein, for simplicity) of cellular wirelesscommunication controllers of different cellular communication systemtypes such as PDC and GSM, for example.

FIG. 4 shows generally a dual-mode mobile telephone terminal apparatus200 of the second embodiment of the present invention.

As shown, components identical to those described with reference to FIG.1 in connection with the first embodiment are designated with the samereference numerals, and the discussion about them is not repeated, andcellular wireless communication controllers 8 a and 8 b are differentfrom each other, for example, PDC and GSM, respectively, and arerespectively provided with CPUs 10 a and 10 b and LCD/keypad junctionunits 14 a and 14 b for cellular communications. The rest of theconstruction of the second embodiment remains unchanged from that of thefirst embodiment, and the components identical to those in the firstembodiment are designated with the same reference numerals and thediscussion about them is not repeated.

Since the dual-mode mobile telephone terminal apparatus 200 of thesecond embodiment is equipped with the cellular wireless communicationcontrollers 8 a and 8 b of different cellular communication systemtypes, cellular communications are performed by selecting between thecellular wireless communication controllers 8 a and 8 b.

The dual-mode mobile telephone terminal apparatus 200 of the secondembodiment has the same advantage as that of the first embodiment, andis compatible with two cellular communication system types or more.

(3) Third embodiment

FIG. 5 shows generally a dual-mode mobile telephone terminal apparatus300 of a third embodiment of the present invention.

The second embodiment employs one interfacing means for each of thecellular communication system types mounted while the dual-mode mobiletelephone terminal apparatus of the third embodiment splits, into twofunctions, the interfacing function performed between CPU 3 in thesatellite wireless communication controller 2 and each of the LCD/keypadjunction units 14 a and 14 b in the respective cellular wirelesscommunication controllers 8 a and 8 b, and the software interfacingexecuted by CPU 21 f (see FIG. 3) in the first embodiment under thecontrol of the program is carried out by common first interfacing means23, while the electrical interfacing executed by the address decoders 21a and 21 d and the input output ports 21 b, 21 c and 21 d in the firstembodiment is performed by second interfacing means 22 a and 22 b of therespective cellular wireless communication controllers 8 a and 8 bcorresponding to the respective cellular communication systems.

No further description using drawings is provided for the thirdembodiment, and the first interfacing means 23 includes a CPU havingsubstantially the same function as that of CPU 21 f in the interfacingmeans 21 in the first embodiment, and when the cellular wirelesscommunication controllers are mounted, the cellular communicationsystems of the cellular wireless communication controllers 8 a and 8 bto be used are set using DIP switches (not shown) and a mode settingsignal for each cellular communication system set is output and inresponse to the mode setting signal, the first interfacing means 23makes software interfacing by switching the program for data formatconversion and other processes, which is executed by CPU 21 f in thefirst embodiment, to match the cellular communication systems, and thesecond interfacing means 22 a and 22 b are provided with the addressdecoders 21 a and 21 d and the input and output ports 21 b, 21 c and 21e for respective cellular communication systems to make electricalinterfacing. The rest of the construction of the third embodimentremains unchanged from that of the second embodiment, and componentsidentical to those described with reference to FIG. 2 in connection withthe second embodiment are designated with the same reference numerals.

For this reason, the dual-mode mobile telephone terminal apparatus 300of the third embodiment has the same advantage as that of the secondembodiment, and the hardware of the first interfacing means 23 formaking software interfacing for data format conversion and otherprocesses is shared by the cellular communication systems, reducing thecost of the apparatus.

In the second embodiment, the second interfacing means 22 a and 22 b arerespectively arranged for the cellular wireless communicationcontrollers 8 a and 8 b of different cellular communication systemtypes, but when the electrical specifications of the cellular wirelesscommunication controllers 8 a and 8 b are identical even with theircellular communication system types being different, a single secondinterfacing means commonly works for the two. The same is true of thefollowing embodiments.

(4) Fourth embodiment

FIG. 6 shows generally a dual-mode mobile telephone terminal apparatus400 of a fourth embodiment of the present invention.

Although the dual-mode mobile telephone terminal apparatus 400 of thefourth embodiment employs a single cellular wireless communicationcontroller 8, the dual-mode mobile telephone terminal apparatus 400accommodates a cellular wireless communication controller of a differentcellular communication system type because the dual-mode mobiletelephone terminal apparatus 400 comprises first interfacing means 23for performing software interfacing for data format conversion or otherprocesses under the control of a program, second interfacing means 22 aand 22 b for performing electrical interfacing in accordance with thecellular communication systems of cellular wireless communicationcontrollers expected to be mounted (two controllers herein, forsimplicity), and a selector 24 for selecting one of the outputs of thesecond interfacing means 22 a and 22 b in response to the mode settingsignal for the type of cellular communication system.

When the cellular wireless communication controller of differentelectrical interfacing specifications is mounted in the dual-mode mobiletelephone terminal apparatus of the fourth embodiment, the cellularcommunication system of the cellular wireless communication controllerto be used is set using DIP switches (not shown) and a mode settingsignal for the cellular communication system is output and in responseto the mode setting signal, the program of the first interfacing means23 is switched to the one compatible with the cellular communicationsystem set, and one of the outputs of the second interfacing means 22 aand 22 b is automatically selected, and the data format conversion andelectrical interfacing are performed in accordance with the cellularcommunication system of the cellular wireless communication controller 8mounted.

The dual-mode mobile telephone terminal apparatus 400 of the fourthembodiment thus assures a wide compatibility, needing no particularmodification, even when a cellular wireless communication controllerhaving different electrical interfacing specifications is mounted.

(5) Fifth embodiment

FIG. 7 shows generally a dual-mode mobile telephone terminal apparatus500 of a fifth embodiment of the present invention.

In the dual-mode mobile telephone terminal apparatus 500 of the fifthembodiment, the software interfacing function performed by the firstinterfacing means 25 under the control of the program is carried out byCPU 3 in the satellite wireless communication controller 2, andspecifically, a program for the process carried out by the firstinterfacing means 23 is added to the program of CPU 3.

The rest of the construction of the fifth embodiment remains unchangedfrom that of the first embodiment, and components identical to thosedescribed in connection with the first embodiment are designated withthe same reference numerals and the discussion about them is notrepeated.

Since the dual-mode mobile telephone terminal apparatus 500 of the fifthembodiment needs no first interfacing means 23, compact and low-costdesigns are implemented in the entire hardware of the apparatus.

(6) Sixth embodiment

FIG. 8 shows generally a dual-mode mobile telephone terminal apparatus600 of a sixth embodiment of the present invention.

In the dual-mode mobile telephone terminal apparatus 600 of the sixthembodiment, CPU 3 in the satellite wireless communication controller 2performs the function carried out by the first interfacing means 26,which makes software interfacing for data conversion and other processesby switching the program in response to the mode setting signal for thecellular communication system, and specifically, the program of thefirst interfacing means 23 is added to the program of CPU 3, and in thesame way as in the dual-mode mobile telephone terminal apparatus 400 ofthe fourth embodiment shown in FIG. 6, the dual-mode mobile telephoneterminal apparatus 600 comprises second interfacing means 22 a and 22 bfor making electrical interfacing for a cellular wireless communicationcontroller of a different cellular communication system with differentelectrical interfacing specifications (two types herein, forsimplicity), and a selector 24 for selecting one of the outputs of thesecond interfacing means 22 a and 22 b in response to the mode settingsignal for the type of cellular communication system.

Even when a cellular wireless communication controller 8 of a differentcellular communication system is mounted in the dual-mode mobiletelephone terminal apparatus 600 of the sixth embodiment, CPU 3functions for the first interfacing means 26 with the program of thefirst interfacing means 26 changed to the one compatible with themounted cellular communication system, and the appropriate one of thesecond interfacing means 22 a and 22 b is automatically selected inresponse to the mode setting signal for the cellular wirelesscommunication controller 8.

In the same way as in the fourth embodiment, the dual-mode mobiletelephone terminal apparatus 600 of the sixth embodiment needs noparticular modification even when the cellular wireless communicationcontroller of different cellular communication system is mounted, andsince CPU 3 in the satellite wireless communication controller 2functions for the first interfacing means 26, there is no need formounting the first interfacing means 26 in hardware, and compared withthe fourth embodiment, the hardware component count of the apparatus isreduced and the entire hardware is made compact and less costly.

(7) Seventh embodiment

FIG. 9 shows generally a dual-mode mobile telephone terminal apparatus700 of a seventh embodiment of the present invention.

In the dual-mode mobile telephone terminal apparatus 700 of the seventhembodiment, second interfacing means 28 for performing electricalinterfacing to a signal from CPU 3 in the satellite wirelesscommunication controller 2 is arranged separately from the satellitewireless communication controller 2 and the cellular wirelesscommunication controller 8, the function of the first interfacing means28 for performing software interfacing for data format conversion andother processes under the control of a program is added to CPU 10 in thesatellite wireless communication controller 2, and specifically, theprogram for performing the process by the interfacing means 28 is addedto the program of CPU 3. The rest of the construction of the seventhembodiment remains unchanged from that of the first embodiment, andcomponents identical to those described in connection with the firstembodiment are designated with the same reference numerals.

Since CPU 10 in the cellular wireless communication controller 8functions for the first interfacing means 28 in the dual-mode mobiletelephone terminal apparatus 700 of the seventh embodiment, there is noneed for arranging the first interfacing means 28 in hardware, and inthe same way as in the fifth embodiment, the hardware component count ofthe apparatus is reduced and the entire hardware is made compact andless costly.

(8) Eighth embodiment

FIG. 10 shows generally a dual-mode mobile telephone terminal apparatus800 of an eighth embodiment of the present invention.

The dual-mode mobile telephone terminal apparatus 800 of the eighthembodiment, like the fourth embodiment, employs a single cellularwireless communication controller 8, and to be compatible with theinstallation of a cellular wireless communication controller of variouscellular communication system type, the dual-mode mobile telephoneterminal apparatus 800 comprises the first interfacing means 28 forperforming software interfacing for data format conversion and otherprocesses under the control of a program in CPU 10 in the cellularwireless communication controller 8 (for two types herein, forsimplicity) expected to be mounted, the second interfacing means 22 aand 22 b for performing electrical interfacing for the cellularcommunication system of the cellular wireless communication controller 8expected to be mounted, arranged separately from the satellite wirelesscommunication controller 2 and the cellular wireless communicationcontroller 8, a selector 24 for selecting one of the outputs of thesecond interfacing means 22 a and 22 b in response to the mode settingsignal for the type of cellular communication system.

Even if the dual-mode mobile telephone terminal apparatus 800 of theeighth embodiment has a cellular wireless communication controller 8 ofa different cellular communication system, like the fourth embodiment,the appropriate one of the second interfacing means 22 a and 22 b isautomatically selected in response to the mode setting signal for thecellular wireless communication controller 8.

Even when the cellular wireless communication controller 8 of adifferent cellular communication system type is mounted in the dual-modemobile telephone terminal apparatus 800 of the eighth embodiment, thedual-mode mobile telephone terminal apparatus 800 is compatible with thedifferent cellular communication system type with no particular hardwaremodification required, as long as the electrical interfacingspecifications of the cellular communication system are compatible withthe second interfacing means 27 a and 27 b.

Since the function of the first interfacing means 28 for performingsoftware interfacing for data format conversion and other processesunder the control of a program is performed by CPU 10 in the cellularwireless communication controller 8 expected to be mounted, there is noneed for a new CPU for carrying out the function of the firstinterfacing means 28, and the manufacturing cost of the apparatus isreduced accordingly.

Industrial Applicability

Since in the dual-mode mobile telephone terminal apparatus of thepresent invention as described above, the interfacing between theinput/output junction such as the LCD/keypad junction unit 14 in thecellular wireless communication controller and the satellite wirelesscommunication controller is performed by the interfacing means ratherthan by the external input/output terminal of the cellular terminalmodule, the hardware modification involved is minimized when cellularwireless communication controllers of a variety of cellularcommunication systems are incorporated, and the resulting reduceddevelopment cost consequently leads an inexpensive dual-mode mobiletelephone terminal apparatus, and no hardware modification is involvedwhen one cellular communication system of cellular wirelesscommunication controller is changed to another cellular communicationsystem.

What is claimed is:
 1. A dual-mode mobile telephone terminal apparatuscomprising a satellite wireless communication controller for performingsatellite communications with another terminal apparatus via acommunications satellite, a cellular wireless communication controller,including an input/output junction unit, for performing cellularcommunications with another terminal apparatus via a ground station, andinterfacing means, arranged between the satellite wireless communicationcontroller and the input/output junction unit of the cellular wirelesscommunication controller, for making interfacing between the satellitewireless communication controller and the input/output junction unit ofthe cellular wireless communication controller, wherein the cellularwireless communication controller outputs in/out-of-area informationthat indicates whether the apparatus is in or out of a cellularcommunication service area while the satellite wireless communicationcontroller receives the in/out-of-area information from the cellularwireless communication controller, and when the satellite wirelesscommunication controller determines that the apparatus is in thecellular communication service area, the satellite wirelesscommunication controller causes the cellular wireless communicationcontroller to perform cellular communications, and when the satellitewireless communication controller determines that the apparatus is outof the cellular communication service area, the satellite wirelesscommunication controller performs satellite communications.
 2. Adual-mode mobile telephone terminal apparatus comprising a satellitewireless communication controller for performing satellitecommunications with another terminal apparatus via a communicationssatellite, a cellular wireless communication controller, including aninput/output junction unit, for performing cellular communications withanother terminal apparatus via a ground station, and interfacing means,arranged between the satellite wireless communication controller and theinput/output junction unit of the cellular wireless communicationcontroller, for making interfacing between the satellite wirelesscommunication controller and the input/output junction unit of thecellular wireless communication controller, further comprising aplurality of cellular wireless communication controllers of differentcellular communication system types, first interfacing means for makingsoftware interfacing under the control of a program compatible with thecellular communication system of one cellular wireless communicationcontroller in use, out of the plurality of cellular wirelesscommunication controllers, and a plurality of second interfacing means,respectively arranged for the plurality of cellular wirelesscommunication controllers, for performing electrical interfacing,wherein when one of the plurality of cellular wireless communicationcontrollers performs cellular communications, the first interfacingmeans makes software interfacing under the control of the programcompatible with the cellular communication system of the one cellularwireless communication controller while the second interfacing meansmakes electrical interfacing compatible with the one cellular wirelesscommunication controller, in connection with the interfacing activitybetween the satellite wireless communication controller and theinput/output junction unit of the cellular wireless communicationcontrollers.
 3. A dual-mode mobile telephone terminal apparatuscomprising a satellite wireless communication controller for performingsatellite communications with another terminal apparatus via acommunications satellite, a cellular wireless communication controller,including an input/output junction unit, for performing cellularcommunications with another terminal apparatus via a ground station, andinterfacing means, arranged between the satellite wireless communicationcontroller and the input/output junction unit of the cellular wirelesscommunication controller, for making interfacing between the satellitewireless communication controller and the input/output junction unit ofthe cellular wireless communication controller, further comprising, inthe interfacing means, first interfacing means for making softwareinterfacing under the control of a program compatible with the cellularcommunication system of one cellular wireless communication controlleractually mounted, out of a plurality of cellular wireless communicationcontrollers of different cellular communication system types expected tobe mounted, a plurality of second interfacing means, respectivelyarranged for the plurality of cellular wireless communicationcontrollers, for performing electrical interfacing, with the firstinterfacing means arranged separately from the plurality of secondinterfacing means, and selection means for selecting one secondinterfacing means, among the plurality of second interfacing means,compatible with the mounted cellular wireless communication controller,wherein when one of the plurality of cellular wireless communicationcontrollers performs cellular communications, the first interfacingmeans makes software interfacing under the control of the programcompatible with the cellular communication system of the one cellularwireless communication controller, while the second interfacing meansmakes electrical interfacing compatible with the one cellular wirelesscommunication controller selected by the selection means, in connectionwith the interfacing activity between the satellite wirelesscommunication controller and the input/output junction unit of thecellular wireless communication controllers.
 4. A dual-mode mobiletelephone terminal apparatus according to claim 3, wherein the CPU thatexecutes the program in the satellite wireless communication controllerto perform satellite communications further makes software interfacingunder the control of the program of the first interfacing means for thefirst interfacing program.
 5. A dual-mode mobile telephone terminalapparatus according to claim 3, wherein the CPU that executes theprogram in the cellular wireless communication controller to performcellular communications further makes software interfacing of the firstinterfacing means for the first interfacing means.